Process for briquetting wood particles and product thereof



Patented Apr. .13, 192a.

UNITED STATES PATENT OFFICE.

HALL H. HOLDAWAY OE LOS ANGELES, CALIFORNIA, ASSI GNOB 'I'O LEROY I. PIKE AND A. B. FLICKINGER, BOTH OF RENO, NEVADA.

No Drawing.

To all whom it concern:

Be it known that I, HALL H. HOLDAWAY,

' citizen of the United States, residing at Los Angeles, county of Los Angeles, State of California, have invented new and useful Improvements in Processes for Briquetting Wood Particles and Product Thereof, of which the following is a specification.

My invention has for its object the compacting into briquets of cellulose material,

such as sawdust, wood pulp, shavings and the like, and this object I attain by compressing the wood material under conditions of predetermined initial and final temperatures and pressure. a

In some instances to secure a superior result I have also found it advantageous to treat the material during the process steps with a gaseous mixture which appears tohave the quality of softening the surfaces of the particles so that under pressure the surface fibre of the adjacent particles more securely interlocks or binds together thus forming an integral mass in the press, which retains its shape and dimensions'when released.

I do not employ any binder or other'material toefl'ect a cementation between the.

particles, but rather I treat theparticles by conditioning their surfaces such that they will adhere to adjacent similarly heated particles when-brought together in intimate contact by pressure.

I have found that when the comminuted ,Wood particles are dried by expelling the entrained moisture and are then preheated and the temperature further increased during actual contact between the surfaces of the particles an adherence of the particles results to a degree suflicient to form a briquet of permanence, (efficiency and commercial value. 7

While my process is adapted to various woods, I have chosen below a specific example of its employment in connection with Oregon pine shavings or sawdust or will waste as a raw material. This is first thoroughly dried by any conventional means, and I have found that blowing the material through a tube or compartment with dry .hot air is sufficient. After the raw ma.-

lpplication filed January 21, 1925. Serial lilo. 3,796.

terial is dried is brought up to a heat of about 300 Fahrenheit and this may advantageously be a continuation of the. drying step.

While in this heated condition it is passed directly into a press and rapidl pressed to about one sixth of its normal ree volume. The act of compressing the material results in raising the temperature of the particles while beingpressed together and of the resulting briquetted mass to from 450 to 500 Fahrenheit. ,It is under this final extreme heat that the material takes its final set by the particles adhering together in briquet form in the press. Y

The briquet in fact' becomes as hot as possible without actually combusting. The

increase temperature is reached almost instantly during the pressing operation and I the smoking briquets are immediately freed from press and allowed to cool.

As a variation of the above process giving excellent results with certain woods, I inject a chemical gas during, or immediately following the drying step, which gas has a tendency to prepare the outside of each particle of material for interlocking or, agglomeration under the subsequent pressing step. I have found a mixture of alco- 1101, water, formaldehyde and earbolic acid which, when gasified during the drying or preheating step in the presence of the material to the briquetted will increase the adhering qualities of the particles and secure their close' compacting and adherence when the final briquetting pressure and temperature is reached.

As an example of the employment of such a gas in practicing my process, I pass wood shavings and comminuted through-atubular member by blowing the material therethrough with hot dry air, and at the same time I inject into the said compartm'ent less than one one-ten-thousandth mill waste by weight, of a mixture consisting substantially of one partcarbolieiacid, three parts formaldehyde, forty-eight parts alcohol and sixty-four parts of water. The dried and treated shavings are then immediately intro- 1 duced into-a closed chamber and while having an initial temperature of from 250? to 350 Fahrenheit derived from the above drying and preheating, are immediately compressed to about one sixth of their free volume during which the temperature will rise to from 450 to 500 Fahrenheit. The pressure is then relieved and the smoking briquet, so hot that it has changed color on account of commencing to carbonize, is ejected from the press as a finished article.

If preferred, the chemical gas above described may be injected as a gas or may begasified from a minute quantity of the liquid mixture injected into the mass in the press before, or during compression.

I claim:

1. The method of briquetting comminuted wood material which consists of drying the material preheating the material and then while so heated rapidly compressing the materialinto a briquet to substantially one sixth of its free-volume.

2. The method of briquett-ing comminuted wood material which consists of drying the anaterial preheating the material to Sllb.

stantially 300 Fahrenheit and then while so heated rapidly compressing the material into a briquet to substantially one sixth of its free volume.

3. The method of briquetting comminuted wood material which consists of drying the material within an envelope of organic gas, preheating the material and thenwhile so heated rapidly compressing the material into a briquet whereby the temperature during compression is raised above 450 Fahrenheit.

4. The method of briquetting comminuted wood material which consists of drying the material preheating the material and then while so heated rapidly compressing the material into a briquet to substantially one sixth of its free volume whereby the temperature during compression is raised above 450 Fahrenheit.

5. The method of briquetting comminuted wood material which consists of drying the material preheating the material to substantially 300 Fahrenheit within an envelope of organic gas and then while so heated rapidly compressing the material into a briquet whereby the temperature during compression 1s raised above 450 Fah- 'renheit.

6. The method of briquetting comminuted wood material which consists of drying the material preheating the material to substantially 300 Fahrenheit and. then while so heated rapidly compressing the material into a briquet to substantially one sixth of its free volume, whereby the temperature during compression is raised above 450 Fahrenheit.

3 7. The method of briquet-ting comminuted wood material-which consists of drying the materialpreheating the material while ex tion of a gas composed of substantially one part carbolic acid, three parts formaldehyde, forty-eight parts alcohol and sixty-four parts of water and then while so heated immediately compressing the material into a briquet.

10. The process set forth in claim 4 wherein during the process the material particles are exposed to the action of a. gas.

11. The process set forth in claim 6 wherein during the process the material particles are exposed to the action of a gas.

12. The process set forth in claim 1 wherein during the process the material particles are exposed to the action of a gas composed of substantially onepart carbolic acid, three parts formaldehyde, forty-eight parts alcohol and sixty-four parts of water.

13. The process set forth in claim 2 wherein during the process the 'material particles are exposed to the action of a gas composed of substantially one .part carbolic acid, three parts formaldehyde, forty-eight parts alcohol and sixty-four parts of water.

14. The process set forth in .claim 3 wherein during the process the material particles are exposed to the action of a gas composed of substantially one part carbolic acid, three parts formaldehyde, forty-eight parts alcohol and sixty-four parts of water.

15. The process set forth in claim 4 wherein during the process the material particles are exposed to the action of a of substantially one part carbo 0 acid, three parts formaldehyde, forty-eight parts alcohol and sixty-four parts of water.

16. The process set forth in claim 5 wherein during the process the material particles are exposed to the action of a gas composed of substantially one part carbolic acid, three parts formaldehyde, forty-eight parts alcohol and sixty-four parts of water.

17. 'The process set 'forth in claim 6 wherein during the. process the material particles are exposed to the action of a gas composed of substantially one part carbolic acid, three parts formaldehyde, forty-eight parts alcohol and sixty-fourparts of water.

18. The method of briquetting comminuted wood material whichconsists of drying the material, and then preheating the material 'in a stream of'organic gas and then lgias composed a while so heated, compressing the material into a briquet of substantially one sixth of the-volume of the comminuted particles.

19. The method of bt'iquetting commi- 5 nuted Wood material which consists of drying the material, then pr terial to substantially 300 eheatin the ma- F'. while confined in an envelope and therefore exposed to the action of an organic gasand then while so heated, immediately compressing the material into a briquet of substantially one sixth of the volume of the comminuted particles HALL H. HOLDAWAY. 

